Black Box is the scientific version of Mastermind. Originally a board game, it transfers well to a computer.

You use your powers of deducation to locate a given number of atoms (up to 10) which are hidden in an 8 x 8 grid. There are 32 rays positioned around the edge of the grid which are used to detect the co-ordinates of each atom, depending on whether a ray is absorbed, deflected or reflected.

When you think you know where the atoms are, you enter your guesses. A score is given based on the proportion of atoms you track down and the number of rays you use.

Understanding exactly how rays are deflected and relected took time to fully comprehend. The instruction give full details on the origins of the game, but provide only a few sentences and one example for the complete beginner.

J.W.